90 day online system is a stand alone automated local system that isn't synced to the main entry/exit database When you complete the TM47 online, it requests your last arrival date in Thailand. For example, if your last entry was 24th July 2024, then you depart for a visit to your homeland on 2nd Feb 2026, you can still complete the online report from overseas, as nothing changes, your last entry date was still 24th July 2024. Indeed you can also continue to submit online reports after returning to Thailand, providing you still enter the same last entry date of 24th July 2024. (Not recommended). However usually once reinterring Thailand again, say 2nd March 2026 and now completing the online form with the new and correct last entry date of 2nd March 2026, then your online application will automatically be rejected due to a change in the information the database already holds on file. After reentry the first 90 day report should be due 89 days after the date of entry, as the date of entry is count one of the 90 days. The reason you have to then report in person is because your new due date is now out of sync with the automated database, and a local IO has to manually reset the next due date into the database.
